I am mostly familiar with Guionnet for his hard-edged saxophone work, but this busy polymath from Lyon does all kinds of stuff. Checking his website, one finds visual art, theoretical material about electro-acoustics and much else — good stuff. And today (May 21), he performed a great solo concert for pipe organ, at this well-appointed Catholic church on the side of Mount Arthabaska.
The history of avant-garde composition for the pipe organ is dominated by Olivier Messiaen, who was an actual church organist early in his career. There are flashes of tone-gush today that recall Messiaen's palette, but most of Guionnet's playing is far more out-there, utilizing the extreme lower range of the organ and taking it to points where all you could hear was the breathing of the organ's bellows echoing through the quiet nave. There were also some spectacularly spacey segments, where the sonics remind me of Varese's piece "Ionisation," composed for the Ondes Martinot (an early precursor to the synthesizer).
Like several of the other long pieces at this festival, Guionnet's composition was circular in nature, beginning and ending with quiet passages that were bridged by slowly escalating structures of tone and quiet fury. It was a beautiful way to spend a Sunday afternoon in church.